https://medlineplus.gov/ency/article/000998.htm
A canker sore is a painful, open sore in the mouth. Canker sores are white or yellow and surrounded by a bright red area. They are not cancerous.
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https://www.mycankersoretreatment.com/
Info on the latest canker sore treatments to relieve pain and inflammation. Learn what may heal them faster, get tips on prevention.
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